blob: cca66686adb5c06593450cac7993354b6e7c74cd (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
|
tcpmssd was written by Ruslan Ermilov <ru@FreeBSD.org> based on work
done by Patrick Bihan-Faou <patrick@mindstep.com>.
tcpmssd is a divert(4) program that adjusts outgoing TCP data so that
the requested segment size is not greater than the amount allowed by
the interface MTU.
This is necessary in many setups to avoid problems caused by routers
that drop ICMP Datagram Too Big messages. Without these messages,
the originating machine sends data, it passes the rogue router then
hits a machine that has an MTU that is not big enough for the data.
Because the IP Don't Fragment option is set, this machine sends an
ICMP Datagram Too Big message back to the originator and drops the
packet. The rogue router drops the ICMP message and the originator
never gets to discover that it must reduce the fragment size or drop
the IP Don't Fragment option from its outgoing data.
|
